COMPOUNDS AND THEIR PROPORTIONS
COMPOUNDS AND THEIR PROPORTIONS All elements are represented by a chemical symbol. It is either a single capital letter, or a capital letter followed by a small letter. Examples: Ca = calcium Cu = copper C = carbon N = nitrogen Combinations of symbols represent compounds. These compounds are called chemical formulas. Example: H20 2 hydrogen atoms 1 oxygen atom If no number is shown beside the symbol, a 1 is understood. If more than 1 atom is present, a small number is shown after the atom to indicate how many atoms are in the compound. NaHCO3 = Sodium Hydrogen Carbonate (baking soda) 1 atom Na = Sodium 1 atom H = Hydrogen 1 atom C = Carbon 3 atoms O = Oxygen See also SIMPLE MACHINE AIR AND COMBUSTION AN ALKALI BASES AND INDICATORS EVAPORATION AND BOILING